Change-speed friction gearing



Aug. 2592?.

1,637,664 w. sToEcKlcHT CHANGE SPEED FRICTION GEARING Filed April 28.-1924 jwereiw:

MAMA/m flame Patented Aug. 2, 1927.

UNITED STATES 1,637,664 PATENT OFFICE.

WILHELM STOEGKICH'I, OF MUNIGH-SOILN, GERMANY.

Cannes-SPEE FRICTION GEARING.

Application filed April 28, 1924, Serial No.

while the transmission of the power takes place. Said ring is,therefore, made, preferably, of a high-grade material. and those of itssurfaces which contact with the friction members and transmit the powerfrom one shaft to the other are. in conformity with the invention, soshaped that said friction members and said ring contact with each other,as far as possible. in a point or on a line, that is to say, on verysmall surfaces. For this purpose the inner and the outer surface of thethrust-ring which are those contacting with the friction-members are soshaped as to be curved or be very narrow so that the theoreticallydesired point contact is practically obtained, although it must, infact, be a contact between flat surfaces. subdivide either the outer orthe inner contact-surface of the thrust-ring, or both contact-surfacesthereof, in such a manner that the contact between a subdivided frictionsurface of the ring and a corresponding friction surface of a frictionbody= takes place simultaneously at several places., The curved shaperenders it possible to allow the thrust-ring to assume a certain slightoblique position, as well as to rotate around an axis extending throughthe points of contact. By subdividing one or all thrust-surfaces thereis attained the result that the forces passing through the ring balanceeach other, and in consequence whereof a rigid guide for the ring can bedispensed with. By the oblique position of the ring which takes placeduring the rotation a shifting of the ring sets in since it is shiftedautomatically until its plane of rotation stands again vertically withrespect to the axis surrounded by it, that is to say, the plane ofrotation of the ring lies then parallel to the planes of rotation of thysurface points ofthe conical friction bodi'es.

My invention is illustrated diagrammatically by way of example in theaccompanying drawing in which Figure 1 is a side-view of a change-speedfriction gearing composed It is suited to the purpose to 709,517, and inGermany February 2, 1924.

of two parallel shafts with known friction ropes. and of a thrust ringdevised and arranged according to this invention; Figure 2 is a plan ofthe arrangement and combination of parts illustrated in Figure 1, andFigure 3 is a radial section through a part of 1the thrust-ring, drawnto an enlarged sca e.

ure 1. the inner contact surface of the thrust-ring 0 is so subdividedthat it con tacts at two points. projections or places 2 and 3 with thefriction surface which it surrounds whereas its outer peripheral surface1 which contacts with the surface of the other friction member isslightly curved, so that it contacts only at one point or proection withthat friction member.

The transmission of the power takes place at three points, namely,relative to the outer periphery of the thrust ring, at a convex orprojected surface on 1, and relative to the inner periphery, at a singlepoint surface 3, as well as at a frusto-conical or projected surface 2.

the change-speed friction-gearing It is im material whether a or b isthe driving shaft, or the driven one respectively. and k are reverselyarranged cones, or conical powcr-transmitting members respectively,which are atfixcd to said shafts. c is the thrust-ring by which thepower is transmitted from the cone is to the. cone is, or revcrsely, asthe case may be, and (Z, d and denote a controland guiding-device for usaid thrust-ring, this device consisting of a body (Z and two parallelannuli d and d which enclose the thrust-ring 0 between them. The ring ais loosely held between the annuli (Z and (Z so that it can rotatefreely between them, together with the cones k and 762. The body d ofthe controland guiding-device (Z, d and (Z2 is hinged by a pin a to athreaded sleeve 7 located on the threaded part of a rotary spindle 9arranged ohliquely with respect to the shafts a and Z), the anglecorresponding preferably to the angle made by the cones 70 and kSupposing, the spindle g be rotated in such a direction that the sleeve7 is moved from the left to the right, then the device d, d and (Z willfirst assume an oblique position and then follow from the leftto theright until its plane stands again at right angles As illustrated in thesectional View, Fig-' ()n the drawing a and b are the shafts of to theaxes of the cones, as before (see the positions indicated by dottedlines in Figure 1).

The manner of operation of this changespeed friction-gearing isasfollows:

If in any given case the "speed of anengine, a machine, a motor-car,etc. shall be changed, the spindle g is rotated in the correspondingdirection so that the sleeve d is shifted correspondingly whereby themembersd, c and d are, in the beginning, caused to assume a certainoblique position. Suping, the sleeve has been shifted from the positionI (Fig. 1) to the position I, then the members d 0 and d which have beenin the position I will first assume, or, more precisely, be caused toassume, the position II and will then-assume automatically by and bytheposition II". The transmission of the power is not interrupted even fora' second and the chan e of the speed proceeds absolutely free of socks. It is, therefore,

possible to change the speed without'disconnecting the gearing from theengine or metor, 'or other source of power, that is to say, the serviceneed not be interrupted.

I claim: 1. A change-speed friction gearing comprising a pair of cones;and a thrust ring for said cones and having a bearing surface for cone,one bearing surface having and presenting to its respective cone aconvex surface and the other bearing surface having and presenting tothe other cone a frusto-conica surface and a convex surface. 2. Achange-speed friction gearing com prising a pair of cones; a thrust rinencircling one of said cones and having a earg surface for each cone,one surface comin grlsin two projected surfaces each being inpen ent ofthe other, and the opposite surface comprising a single projectedsurface; and means for shifting and guiding said ring on the cone.

3. A' change-sped friction gearing comprising 8138,11 of'cones; a thrustring enmenace circling one of said cones and having a hearing surfacefor each cone, one bearing surface being convex and the opposite surfacebein partly a frusto-conical surface and part y conveir; and means forshifting and guiding said ring on the cone.

.4. A change-speed friction gearing comprising a pair of cones, one ofwhich is a driving cone and the other is a driven cone; a thrust ringencircling one of said cones and provided'with a bearing surface foreach cone, one bearing surface being partly a frusto-conical surface andpartly a projected surface and the opposite bearing surface being aprojected surface; and a device for guiding said ring on the cone andfor shifting the position thereof in order to change the speed of one ofthe cones. 1

5. A. change-speed friction gearing comprising a pair of cones; a thrustring'asso 1 ciated with said cones and having a bearing surface for eachcone, one bearing surface comprising partly a projected surface andpartly a frusto-conical surface and the otherbearing surface comprisinga projected surface; and means for shifting and guiding said ring.

6. In a change-speed device for a friction gearing, a thrust ring havinginner and outer bearing surfaces, the inner surface comprising partly aprojected surface and a frusto-oonlcal surface and the opposite surfacecomprising "'a projected surface.

7. In a change-speed device for a friction gearing, a thrust ring havingtwo bearing surfaces, one surface comprising partly a pro ected surfaceanda fI'US'DO-COIIIOfll'SllI face and the other surface comprising apro-' jected surface.

8. In a change-speed device for a friction.

gearing, a thrust ging having two bearingsurfaces, one surface beingconvex and the opposite surface being partly a frusto-conical surfaceand partly a convex surface.

In testimon whereof I alfix my signature.

W ILHELM STOEOKICHT.

